Horizontal motions in sunspot penumbrae

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985815%3A_____%2F22%3A00558170" target="_blank" >RIV/67985815:_____/22:00558170 - isvavai.cz</a>

Výsledek na webu

<a href="http://hdl.handle.net/11104/0332249" target="_blank" >http://hdl.handle.net/11104/0332249</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202243577" target="_blank" >10.1051/0004-6361/202243577</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Horizontal motions in sunspot penumbrae

Popis výsledku v původním jazyce

A model of penumbral filaments represented by magnetoconvective cells was derived recently from spectropolarimetric observations. High-resolution observations of horizontal motions in the penumbra are needed to complement the concept of penumbrae obtained from spectropolarimetry. Time series of images of a large sunspot acquired with the Swedish Solar Telescope are analysed. Horizontal motions of penumbral grains (PGs), structures in dark bodies of filaments, the outer penumbral border, and G-band bright points are measured in time slices. In the inner penumbra, PGs move towards the umbra (inwards) with a mean speed of -0.7 km/s. The direction of motion changes from inwards to outwards at approximately 60% of the penumbral width, and the mean speed increases gradually in the outer penumbra, approaching 0.5 km/s. This speed is also typical of an expansion of the penumbra–granulation border. The majority of the G-band bright points moves away from the sunspot, with a typical speed of 0.6 km/s. High outward speeds, 3.6 km/s on average, are observed in dark bodies of penumbral filaments. According to the model of penumbral filaments, it is suggested that the speeds detected in the dark bodies of filaments are associated with the Evershed flow and that the opposite directions of PG motions in the inner and outer penumbrae may be explained by the interaction of rising plasma in filament heads with a surrounding, differently inclined magnetic field.n

Název v anglickém jazyce

Horizontal motions in sunspot penumbrae

Popis výsledku anglicky

A model of penumbral filaments represented by magnetoconvective cells was derived recently from spectropolarimetric observations. High-resolution observations of horizontal motions in the penumbra are needed to complement the concept of penumbrae obtained from spectropolarimetry. Time series of images of a large sunspot acquired with the Swedish Solar Telescope are analysed. Horizontal motions of penumbral grains (PGs), structures in dark bodies of filaments, the outer penumbral border, and G-band bright points are measured in time slices. In the inner penumbra, PGs move towards the umbra (inwards) with a mean speed of -0.7 km/s. The direction of motion changes from inwards to outwards at approximately 60% of the penumbral width, and the mean speed increases gradually in the outer penumbra, approaching 0.5 km/s. This speed is also typical of an expansion of the penumbra–granulation border. The majority of the G-band bright points moves away from the sunspot, with a typical speed of 0.6 km/s. High outward speeds, 3.6 km/s on average, are observed in dark bodies of penumbral filaments. According to the model of penumbral filaments, it is suggested that the speeds detected in the dark bodies of filaments are associated with the Evershed flow and that the opposite directions of PG motions in the inner and outer penumbrae may be explained by the interaction of rising plasma in filament heads with a surrounding, differently inclined magnetic field.n

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Astronomy & Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Svazek periodika

662

Číslo periodika v rámci svazku

May

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

6

Strana od-do

A13

Kód UT WoS článku

000803310700007

EID výsledku v databázi Scopus

2-s2.0-85131254009